This is just in my personal opinion, and I cannot speak directly of the facility you're referring to as I'm unfamiliar with it.
All of that said, what you want to look for in any vault or storage facility is that they're not a bank as such - as an example, if you stored your bullion in a safe deposit box in a bank, and you have a Cyprus type event occur, you can't get to your bullion. And the content of your safe deposit box in the bank is subject to confiscation.
On that basis, look for a private company who offers this type of service. They should also offer insurance, I would strongly recommend taking it. And, fairly obviously, do your research into the company first - how long have they been in business, are they profitable, what do other users say about them etc.